Q:

Given the system of equations presented here:2x + 4y = 14 4x + y = 20Which of the following actions creates an equivalent system such that, when combined with the other equation, one of the variables is eliminated? Multiply the second equation by −4 to get −16x − 4y = −80Multiply the second equation by −1 to get −4x − y = −20Multiply the first equation by 2 to get 4x + 8y = 28Multiply the first equation by −1 to get −2x − 4y = −14

Accepted Solution

A:
2x + 4y = 14
4x + y = 20......multiply by -4
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2x + 4y = 14
-16x - 4y = -80 (result of multiplying by -4)
---------------add
-14x = -66....as u can see, ur y's cancel out

so ur answer is : 1st answer choice <==

** and just so u know, u could have multiplied the 1st equation by -2, and it would have cancelled out ur x's